This project is concerned with studying systematically the host-parasite interactions in the normal and high-risk pregnant patient. Specifically, we are focusing our efforts on establishing the chemiluminescence response in leukocytes collected from pregnant patients. Since we are a Level III high-risk referral center, it is anticipated that a good number of high-risk pregnant states will be studied. Further, we will explore the possible relationship between the microbicidal and cytotoxic activity of the peroxidase-H2O2-halide system to high-risk pregnancies such as premature rupture of the membranes. Finally, we will attempt to determine the distribution pattern of T and B lymphocytes in pregnancy and the potential relationship to chemiluminescence and host immunity.